出生时的温度和性别比率
Jasmin Abdel Ghany1,2, Joshua Wilde1,2,3,4,5, Anna Dimitrova6
1Nuffield College, University of Oxford, Oxford OX1 1NF, United Kingdom.
概括
怀孕期间暴露于极端热量会显著影响人类出生时的性别比率 (SRB). 气温上升与撒哈拉以南非洲的自发堕胎增加以及印度的性别选择性堕胎减少有关.
科学领域:
- 环境健康 环境健康
- 生殖流行病学 生殖流行病学
- 人口统计学 人口统计学
背景情况:
- 人类出生时的性别比率 (SRBs) 影响人口动态,反映了母亲健康和社会性别偏见.
- 产前暴露于极端高温是一个潜在的环境压力因素,可能会影响SRB,但经验证据很少.
研究的目的:
- 在撒哈拉以南非洲和印度调查产前热量暴露与出生时性别比率之间的联系.
- 区分自发性和受温度影响的性别选择性流产,使用社会人口统计学因素和儿子偏好的区域差异.
主要方法:
- 分析了33个撒哈拉以南非洲国家和印度500万活产婴儿的调查数据.
- 将出生数据与高分辨率温度数据联系起来,以评估产前热暴露.
- 利用社会人口学差异,暴露时间和区域性偏好来区分堕胎类型.
主要成果:
- 在这两个地区,超过20°C的最高温度与男性出生有负面关联.
- 在撒哈拉以南非洲,第一季度的热量暴露与较少的男性出生相关,这表明自发流产的增加,特别是在脆弱的母亲群体中.
- 在印度,第二个三个月的热量暴露与较少的男性出生有关,这与性别选择性堕胎的减少一致,特别是在高阶分娩和在有强烈儿子偏好地区的母亲中.
结论:
- 产前暴露于热量会对母亲的健康产生不利影响,并增加产前死亡率,影响计划生育行为.
- 自发性和性别选择性流产的温度变化导致出生时人类性别比率的复杂变化.
- 环境热量是影响生殖结果和人口性别组成的重要因素.
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